Method for measuring calcium constituent in silicon aluminum calcium barium alloy

The invention discloses a method that is used for measuring the calcium element in a silicon, aluminum, calcium and barium alloy and comprises the following steps: a test sample is placed in a beaker, and deionized water is added until the test sample is wet; 9.5 to 10.5 millimeter of nitric acid is added; 1 to 2 millimeter of hydrofluoric acid is titrated; the mixture solution is heated until completely dissolved; perchloric acid is added; the mixture solution is heated until the sample volume is reduced to 1 to 2 millimeter; the mixture solution is naturally cooled; the perchloric acid is further added, and the mixture solution is heated until the sample volume is reduced to 1 to 2 millimeter; the hydrochloric acid and the deionized water are further added; the mixture solution is heated until all salts are dissolved, and the mixture solution is naturally cooled until the temperature is lower than 40 DEG C; the test sample is placed into a volumetric flask with scales and diluted with the deionized water; a mother solution is placed into a trigonal cup, the deionized water, trolamine (1 added by 1), lemery, bitter salt and an calcon-carboxylic acid are added, and the mother solution is adjusted to be red with potassium hydroxide; the potassium hydroxide is further added; EDTA is titrated until an end point that the mother solution becomes blue; an analyzing result is computed. The method does not need precipitation separation and filtration, and has the acute end point without intermediate color and raised measuring accuracy.